Semiconductor Optoelectronics Laboratory

The well-equipped solid state physics laboratory in the Department permits the performance of experiments on electrical, thermal, optical and acoustical properties of solids. These experiments have been important complements to research in the positron annihilation and magnetic resonance labs. Equipment in the solid state lab includes: induction furnace, high-vacuum equipment, sputtering apparatus, helium cryostats, optical spectrometers and dielectric-loss apparatus.

The major equipment in the optoelectronics laboratory includes a very low background computer controlled cryogenic monochromator, a continuous flow cryostat, a closed cycle refrigerator system, a CO2 laser system, a Fourier Transform Infrared spectrometer (FTIR), a wedge wire bonder, high vacuum system, a 32-channel (25 MHz) logic analyzer with a 2-channel 400MHz (4K memory) digital scope, a circular variable Infrared filter system and a liquid helium cooled bolometer/dewer setup. The data acquisition systems in the laboratory are fully computer controlled via CAMAC (Computer Automated Measurement, Acquisition and Control) and/or IEEE-488 (GPIB–General purpose Interface Bus) interfaces. Some of the CAMAC modules in the system include Gate delay generators, Transient recorders, Scalars, A/D and D/A converters, multiplexers, and LAM generators. The DMA (direct memory access) crate controller in this system permits very fast data transfer. In addition to the optoelectronic research, these systems are used for time interval measurements in connection with non-linear dynamics and neural network research. The modelling and data acquisition is carried out using 386 and 486 (50, 66, 100 MHz) microcomputers with graphic displays and peripherals (plotters, laser printers and a scanner) with a high speed link to a Silicon Graphics computer and the GSU main computer. AutoCAD (a drawing program), QuattroPro (a spreadsheet program), and LaTex (a typesetting program) are used in drawing and document preparation.